Tool for cutting tough elements

ABSTRACT

A small hand-held tool has a concavely open, center-symmetric, cutting edge at a forward end. To cut an elongate object such as a woody weed stem in a garden, the cutting edge is forcibly applied, preferably horizontally, at about or just below ground level in a forward direction simultaneously with an alternating side-to-side horizontal force to turn the tool and the cutting edge in a to-and-fro motion around the elongate object being cut. Forwardly inclined, center-symmetrically disposed saw teeth on the cutting edge will quickly cut the woody stem below ground so that no stubs are left sticking out of the ground to later trip the unwary. If the tool is fitted instead with a cutting blade provided with, for example, tungsten carbide-tipped teeth, or even a toothless edge coated with a layer of tungsten carbide grit, a patient user could apply the thus adapted tool to cleanly cut through much harder objects like steel bars or pipes, e.g., right where they are projecting from a wall or a concrete floor.

FIELD OF THE INVENTION

This invention relates to a small, inexpensive, manual tool for cuttingtough elongate elements in awkward places. More particularly, oneembodiment of the invention relates to a small, hand-held, garden toolwith which a user can quickly and easily cut woody stems and the like,at or a little below ground level, e.g., to neatly clear a garden areaof unwanted vegetation such as brush and mature weeds without having touproot them. With appropriate choice of a cutting blade in the tool, anda little patience, a user can adapt the same tool to cleanly cut muchtougher elongate elements like metal bars or pipes, very close to wherethey project from walls or are embedded in concrete, e.g., after anatural disaster or fire.

BACKGROUND OF THE RELATED ART

Gardeners, real estate developers, and groundskeepers in general, oftenencounter tough woody stems and mature weeds that are very hard to cutdown so close to the ground that they do not leave unsightly andpotentially dangerous stubs sticking out to trip the unwary. Personsfacing this task often use strong shears, or struggle with either a handsaw or a power saw, to do what they can.

Manual shears capable of cutting woody stems up to an inch acrossrequire considerable strength and dexterity to use effectively, they areheavy to lug around over rough or hilly terrain, and tend to beexpensive—posing a serious problem if they are stolen from a work sitewhile the user is otherwise occupied or distracted. A conventionalhand-held saw, flat-bladed or in a frame, is very inconvenient to use atground level. A power saw or trimmer, because it typically has a bulkymotor housing, is likewise hard to use to effect cuts close to ground.Furthermore, an electrical device requires a power supply and posessafety challenges if the ground is wet or when it is likely to rain. Agasoline-powered trimmer, chain-saw, or the like is equally unwieldy andrisky to use at ground level, especially if the ground is wet and muddy.Since groundskeepers, gardeners, and landscape workers generally cannotexpect much sympathy from their employers about such issues they oftenhave to struggle to do the clearing correctly.

On occasion, e.g., after a hurricane or fire, a rescue worker or arsoninvestigator on damaged property might encounter twisted metal in adamaged structure. Even under such trying circumstances, this inventionallows untrained and not particularly strong individuals, willing toexercise a little patience and a suitable blade, to adapt the tool tocut very tough elongate items like steel bars and metal pipes very closeto where they project out of concrete floors or walls without leavingobtruding and potentially dangerous stubs.

The present invention is small but highly versatile, can be quicklyadapted for use in emergencies, under difficult conditions and in tightquarters, and addresses these and other related needs inexpensively,effectively and easily.

SUMMARY OF THE INVENTION

It is a principal object of this invention to provide a lightweight,inexpensive and versatile tool that can be applied even by an untraineduser to quickly and cleanly cut through elongate items, e.g., toughwoody stems at or just below ground level to clear an area of weeds andunwanted vegetation or metal bars or pipes projecting from a wall orfloor after a natural disaster or fire.

This object is realized by providing a hand-held tool having an elongatebody attached to a transverse handle at a proximal end and to an openbracket at a distal end that has a concavely open cutting blade securedtherein.

It is another related object to provide such a tool with blade-mountingstructure at the bracket that allows a user to remove or replace anexhausted cutting blade, or to adapt the tool by mounting to it aspecific cutting blade deemed best suited for cutting a particularelongate object.

This object is realized by providing in the bracket either a recess or agroove shaped to closely accommodate a cutting blade, and correspondingmeans to securely mount a selected cutting blade thereat.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 is a schematic side elevation view of a first embodiment of theinvention being applied to cut an upright woody stem a little belowsurrounding ground level.

FIG. 2 is a downwardly directed plan view of a shorter version of thetool according to the first embodiment, comprising an exemplary firstconcavely open, center-symmetric, cutting blade provided withforward-leaning teeth on a semi-circular cutting edge, as applied to cutan upright woody stem.

FIG. 3 is a plan view of an exemplary second concavely open,center-symmetric, cutting blade for the tool, comprising a pair ofintersecting straight cutting edges each having forward-leaning teeth,wherein the blade has an irregular outer periphery and a single centeredaperture.

FIG. 4 is a plan view of an exemplary third concavely open,center-symmetric, cutting blade for the tool, comprising a set offorward-leaning teeth on an arcuate cutting edge, wherein the blade hasan arcuate outer periphery and a plurality of apertures.

FIG. 5(A) is a plan view of an exemplary fourth concavely open,center-symmetric, cutting blade for the tool, comprising an arcuatecutting edge coated with a cutting grit, wherein the blade has arectangular periphery and a plurality of apertures; and FIG. 5(B) is across-sectional view through the same cutting blade at Section I-I.

FIG. 6(A) is a schematic plan view of the bracket portion of the tool toexplain a structure in which a cutting blade with an irregular arcuateouter periphery is retained within a recess; and FIG. 6(B) is across-sectional view thereof at Section II-II.

FIG. 7(A) is a plan view of the bracket portion of the tool to explain astructure in which a cutting blade with a rectangular periphery isretained within a groove; and FIG. 7(B) is a cross-sectional viewthereof at Section III-III.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

As best seen in the side elevation and plan views per FIGS. 1 and 2,respectively, a preferred embodiment of this invention has the form of ahand-held tool 100 with an elongate body 102, an open bracket 104 at afront end, and a handle 106 at a rear end.

The tool may be made of a metal, a composite or a strong hard plasticsmaterial, to any convenient size, using known manufacturing techniques.A preferred overall length for use as a garden tool is in the range 8-14in., with a handle width in the range about 7-10 in. Bracket 104preferably has both a width and a depth in the range 2-3 in. These aremerely preferred dimensions, and are not intended to be limiting.

A user of tool 100 would hold handle 106 with both hands and apply thebracket end to an elongate object like an upright woody stem 108 of anundesired weed that is to be cut off at or a little below ground level110 so that no potentially problematic stub is left behind tosubsequently trip an unwary person walking past.

As best seen in FIG. 2, in this embodiment handle 106 is straight andhas two equal arms 116 a, 116 b extending perpendicular to body 102. Itmay suit some users to have the two halves be somewhat inclined to eachother (not illustrated for conciseness). Handle arms 116 a, 116 b may befitted with respective rubber or plastic sleeves 118 a, 118 b,preferably with small bumps or ridges 120, to ensure that the user has anon-slip grip even when working in a wet and/or muddy environment.

Bracket 104, preferably inclined at an angle of up to 45 degreesrelative to body 102, has two equal branches 112 a, 112 b, havingrespective distal ends 114 a, 114 b, and is formed to be symmetric aboutlongitudinal axis A-A of body 102. It holds a cutting blade 200 that hasa concavely open, center-symmetric, cutting edge 202 provided withforward-leaning teeth 222.

The term “concavely open” means that cutting edge 202 is shaped so thatits laterally outermost ends 204 a, 204 b are located apart withinsymmetric bracket arms 112 a, 112 b, and during use are disposedforwardly. This provides a path of entry to receive the object 108 (thatis to be cut by tool 100) into the middle concave opening 206 thusdefined by cutting edge 202.

The term “center-symmetric” is intended to clarify that cutting edge 202is symmetric about its center. This is to ensure that the cutting action(described below) that will be generated by the user will be of equaleffect on both sides of the object being cut.

The term “forward-leaning teeth” means that the teeth are cut so thattheir leading sharpest cutting points and edges are oriented to do cutmost effectively when the teeth move forwardly into a work-piece. Theteeth on opposite sides of the central axis plane of a center-symmetriccutting blade like 202 will be mirror images of each other Consider, forexample, that in using an ordinary hacksaw one places the blade suchthat its “forward-leaning teeth” do the cutting almost exclusively onthe forward stroke. The return stroke with such a hacksaw no doubt doessome cutting but that is almost insignificant compared to what the“forward-leaning” teeth do when forced forward onto the work-piece. Itshould also be understood that, just as with conventional linear orcircular “disk” saws, alternate teeth in all toothed saw bladesconsidered suitable in this invention also lean outward on oppositesides of the cutting blade to help clear cut-off particles thatotherwise would clog and bind the saw blade in the cut that it ismaking.

Note that the outer periphery 208 of blade 200, as shown by broken linesin FIG. 2, has a somewhat irregular arcuate profile that includes acentral extension 210 with a through aperture 212. One inexpensivetechnique for mounting blade 200 to the tool is to mold or otherwiseintegrate it into bracket 104, and in this option the irregularities 214and extension 210 cooperate to help positively secure blade 200 tobracket arms 112 a, 112 b. A small screw or locater pin (not identifieddue to scale) may be placed in aperture 212 to further ensure againstseparation of blade 200 from bracket 104. Note that the principal forceexerted during use is directed forward so that the reaction force fromobject 108 will tend to push blade 200 backward into bracket 104. Theexpressed concern therefore has to do mainly with occasional impacts onbracket 104 that might generate separation-promoting forces. Tool 100with its cutting blade 200 integrated into bracket 104 is obviouslygoing to be somewhat limited in the objects it can be used to cut.

To make the tool more versatile by being able to exchange blades fordifferent cutting tasks it is necessary to make the bracket structure alittle more sophisticated. Factors to be considered include alternativeshapes for the blade element, optional cutting edge structures forcutting materials of different hardness, and alternative ways ofsecuring a blade to the tool bracket. The numerous permutations of suchfeatures allow for creative combinations to suit a wide array ofapplications to address different needs. This aspect of the inventionmakes the tool both highly versatile and easily adaptable for urgentuse, and therefore an important addition to many personal toolinventories.

FIG. 3 is a plan view of a cutting blade 300 that has center-symmetricarms 330 a, 330 b with respective ends 332 a, 332 b. It also has anirregular periphery 308 similar to that of cutting blade 200 discussedabove, including central extension 310, aperture 312, and a plurality ofirregularities 314. Cutting blade 300 has a V-shaped concavely open,center-symmetric, cutting edge comprising a pair of intersecting linearportions 320 a, 320 b that meet at center 322 which will be located inthe vertical plane of longitudinal axis A-A of the tool when cuttingblade 300 is mounted for horizontal application in use.

FIG. 4 is a plan view of a cutting blade 400 that has a concavely open,center-symmetric, arcuate cutting edge 402 with a generally parabolicprofile (unlike the semicircular profile of cutting edge 202 discussedearlier with reference to FIG. 2). Cutting blade 400 has a pair of arms412 a, 412 b with respective ends 414 a, 414 b, and a smoothly arcuateouter periphery 408. It has a plurality of through apertures 420distributed inside periphery 408.

FIG. 5(A) is a plan view of a cutting blade 500 that differs fromcutting blade 400 in having a rectangular outer periphery 508 instead ofan arcuate one. It does, however, have an arcuate cutting edge 502.Cutting blade 500 has a plurality of through apertures 520 through whichscrews are passed to secure it to a matching tool bracket.

Conventional “high carbon” steel saw blades with forward-leaning teethwill cut many commonly encountered materials, e.g., wood, plastics, andsome of the softer metals like brass, copper and iron. Toothed cuttingblades suitable for use in the present invention may be made ofconventional case-hardened steel just like hacksaw blades and the like.However, if a saw of any kind is to be used to cut hard steel, it isadvisable to have the saw teeth tipped with tungsten carbide tips thatare singularly hard, can be sharpened with a diamond dressing wheel whenneeded, and are relatively inexpensive but very durable. This choice isrecommended for cutting blades to be used in this invention for cuttinghard materials.

As previously mentioned, one may occasionally need to cut steel bars instorm or fire-damaged property. Such objects might be exposed from awall or concrete and have very hard sand and/or cement particlesstrongly adhered to them. Even a carbide-tipped saw tooth might crack ifused with less than extreme care under such circumstances, but a cuttingblade coated with a layer of carbide or diamond grit could be used verycomfortably to cut through both steel and concrete. Considerations ofcost might make diamond grit impractical for some users, but tungstencarbide grit-coated cutting blades are affordable and could bebeneficially included in a set of cutting blades owned by most users ofthis invention. Their use may require some patience, but as indicated inFIGS. 5(A) and 5(B), such cutting blades are a viable option underspecial circumstances.

As best seen in FIG. 5(B), such an abrasive grit coating 550 will givethe cutting profile a thickness “T” that is a little more than theparent blade thickness “t”. This should pose no problem, and in factwill allow particles of cut-off material to slide away without bindingthe cutting blade during use.

There are other alternatives to simply integrating the cutting bladeinto the bracket part of the tool. One such structure is as shown inFIGS. 6(A) and 6(B). As schematically indicated in FIG. 6(A), in a tool600 the bracket 602 is formed to have a recess 610 with a periphery thatmatches in shape and size a corresponding outer periphery 622 of acutting blade 620 comparable to cutting blade 300 (best seen in FIG. 3).This irregular periphery 622 includes a central extension 624. Thethickness of cutting blade 620 should be slightly larger than the depthof recess 610. Cutting blade 620 has an aperture 626 through centralextension 624.

A blade-retaining cover 628 has an outer periphery that matches that ofbracket 602, and extends inwardly to definitely cover and extendinwardly over the irregular periphery of cutting blade 620.Blade-retaining cover 628 is provided with a plurality of throughapertures 630. A number of small screws 632 are tightened throughapertures 630 into corresponding threaded holes 634 provided to receivethem in bracket 602 beneath cutting blade 620. When the screws aretightened in place, cutting blade 620 is securely connected to bracket600 by the force exerted by screwed-down retaining cover 628 and theclose fit between the irregular outer periphery of cutting blade 620 andthe matching periphery of recess 610. Concavely open, center-symmetriccutting edge 650 (shown equipped with forward-leaning teeth) now becomesavailable to cut an object that it is applied to as described above.

In yet another alternative structure, a tool 700 has a bracket 702provided with a peripheral interior groove 704 shaped and sized to veryclosely fit to the outer periphery 706 of a rectangular cutting blade708 that has a plurality of through apertures. The selected blade 708 isshown in FIGS. 7(A) and 7(B) in plan and cross-sectional views,respectively, as having a grit-coated cutting edge 710 that has anarcuate profile. Screws 712 are applied to pass through correspondingapertures formed in cutting blade and then threaded and tightened intothreaded holes provided in bracket 702 underneath. Cutting blade 708will experience only a strong forward force principally along centralaxis A-A, so neither screws 712 nor the arms of bracket 702 be seriouslystressed and they should securely retain cutting blade 708 in bracket702 until the user decides to remove and/or replace it.

Is should be clear that a manufacturer can make cutting blades in anumber of ways to fit a particular bracket and also that the blades canbe selectively installed to perform different cutting tasks as and whenthe user wishes. Such tool and blades sets can be sold as modular kits.In the alternative, a user can simply buy the basic tool and thenseparately buy and install cutting blades to it to perform specifictasks as needed.

The tool is used as follows, regardless of the cutting blade chosen bythe user:

Step 1: select and install a suitable cutting blade in the tool, asappropriate for a given task. Obviously, if a suitable blade is alreadypermanently affixed to the tool then it should be used, otherwise a toolwith the appropriate blade should be chosen.

Step 2: apply the cutting edge to the elongate object that is to be cut,by firmly pressing it forward where the cut is to be made, as indicatedby arrow “F” in FIG. 1. If it is an upright object then the cuttingblade should be held horizontal; in general it should be approximatelynormal to a longitudinal direction of the object where the cut is to bemade.

Step 3: continue to press forwardly on the object with both hands onhandle 106, as indicated by arrows “FR” (force with left hand) and “FL”(force with right hand), while simultaneously applying a to-and-froforce comprising alternating force components “SR” (sideways right) and“SL” (sideways left) to cause the tool to oscillate through an anglepreferably about 90 degrees total around the object being cut. This willcause forced engagement by the forward-leaning teeth of the cuttingblade into the material of the object being cut—first on one side of theobject and then on the other. The result will be a series of cuttingactions into the object principally from two sides. This will be truewhether the cutting edge has teeth or abrasive grit doing the actualcutting.

Note that once the cut has advanced a little, the bottom surface of thecutting blade will be supported and guided by the base of the advancingcut in the object being cut, and this should facilitate faster cuttingmovements by the user.

The selected cutting blade should be large enough to allow a cut to bemade through the entire thickness of the object where it is being cut.Even if this is not fully realizable, i.e., a cut through the entirethickness of the object is not possible with a particular cutting blade,making the cut through a substantial portion of the object may weakenthe remaining portion enough to allow the user to break it off.

As indicated in FIGS. 1 and 2, if a woody stem is to be safely removedit may be appropriate to remove some dirt from immediately around thestem and then make the cut about an inch or more below the surroundingground level. Dirt can be restored after the stem is cut off, and nounsightly and dangerous stub will then be left to trip unwary personspassing by.

If the tool is used to cut off metal bars or pipes projecting from awall or cement floor, a suitable cutting blade must be installed and thecutting done patiently with the bottom of the bracket held close to thewall or floor as the case may be. The cut will remove the offendingobject, and a barely noticeable remnant of the object will be left andthis, hopefully, will not pose a continuing problem.

It should be obvious that the handle can be formed to be in line withthe longitudinal axis of the tool body instead of being made transverseto it. Such a variation of the tool may be useful for some applications,with the user holding the elongate handle with both hands, pressingtowards the cutting edge being applied to an object, and rocking thetool about the object generally as described earlier to effect a cut.

The tool according to this invention in its various embodiments is socompact and light that a competent user should be able to apply it evenin awkward and confined spaces as may be necessary in the aftermath of astorm or fire. A practiced user, e.g., a fireman or rescue worker, maythus find this invention valuable enough to carry along on mostmissions.

Naturally, care must be taken by prison authorities to keep the tool outof the hands of captives who might be tempted to use it to cut throughprison bars and escape.

Persons of ordinary skill in the mechanical arts will no doubt findbenefit in forming various combinations of the different disclosedaspects of this invention to meet particular needs. All suchmodifications of the disclosed invention are intended to be comprehendedin and limited solely by the claims appended below.

1. A manually operable cutting tool for cutting an elongate object,comprising: an elongate body having first and second ends; a handleattached to the first end; an open bracket attached to the second end;and a cutting blade with a concavely open cutting edge, mounted withinthe open bracket.
 2. The tool according to claim 1, wherein: the handleis oriented generally transversely to the body and is configured toprovide a user a secure grip to facilitate application of a forcedirected toward the object accompanied by a rocking force to apply thecutting edge in a to-and-fro cutting motion around the object.
 3. Thetool according to claim 1, wherein: the blade is flat, so that thecutting edge will effect a flat cut along the plane of the blade.
 4. Thetool according to claim 3, wherein: the bracket holds the blade inclinedat a predetermined angle relative to a longitudinal axis of the body. 5.The tool according to claim 4, wherein: the predetermined angle has avalue ranging from 0 to about 45 degrees.
 6. The tool according to claim1, wherein: the cutting blade has a substantially V-shaped cutting edgeprofile comprising two intersecting straight edge portions each providedwith respective forward-leaning teeth to effect the cutting.
 7. The toolaccording to claim 6, wherein: the teeth are provided with tungstencarbide tips.
 8. The tool according to claim 1, wherein: the cuttingblade has a substantially arcuate, center-symmetric, cutting edgeprofile provided with respective forward-leaning teeth on both sides ofthe profile center to effect the cutting.
 9. The tool according to claim8, wherein: the teeth are provided with tungsten carbide tips.
 10. Thetool according to claim 1, wherein: the cutting blade has asubstantially arcuate, center-symmetric, cutting profile provided with alayer of an abrasive grit to effect cutting.
 11. The tool according toclaim 10, wherein: the abrasive grit comprises tungsten carbide.
 12. Thetool according to claim 1, wherein: the cutting blade is permanentlybonded to the tool.
 13. The tool according to claim 1, wherein: thebracket is formed to have a shallow recess shaped and sized to closelyaccommodate the cutting blade, the tool further comprising mountingmeans cooperating with the bracket and the cutting blade to securelymount the cutting blade to the tool inside the recess.
 14. The toolaccording to claim 13, wherein: the cutting blade has an irregular outerperiphery and at least one aperture; the recess has an inner peripherythat closely accommodates the outer periphery of the cutting blade; andthe mounting means comprises a cover element that has a plurality ofapertures and a corresponding plurality of screws passing through theapertures into the bracket, with at least one of the screws passingthrough the cover element and the at least one aperture in the cuttingblade and into the bracket, to thereby secure the cover element and thecutting blade to the tool.
 15. The tool according to claim 1, furthercomprising: a groove formed in the bracket to closely accommodate thecutting blade; and mounting means cooperating with the bracket and thecutting blade to securely mount the cutting blade to the tool inside thegroove.
 16. The tool according to claim 15, wherein: the concavely openblade has a plurality of apertures; and the mounting means comprisesscrews that simultaneously pass through the apertures of the blade andinto the bracket.
 17. A method of manually cutting an elongate object,comprising the steps of: (a) providing a hand-held tool with a cuttingblade that has a concavely open cutting edge capable of cutting theobject; (b) applying the cutting edge to the object where the object isto be cut; and (c) applying to the cutting edge a force directed towardthe object and simultaneously applying a to-and-fro force directedaround the object, to thereby cut the object by alternately traversingthe cutting blade forcefully on different sides thereof.
 18. The methodaccording to claim 17, comprising the further step of: (d) selecting acutting blade sized and shaped to fully accommodate the object withinthe concave opening of the cutting edge during step (c).
 19. The methodaccording to claim 17, wherein: the selected cutting blade comprisescenter-symmetric, forward-leaning teeth.
 20. The method according toclaim 17, wherein: the cutting edge comprises a coating that includes ahard cutting grit.